1.that用作指示代詞的意思是“那,那個(gè)”?？芍盖懊嫣岬降哪羌?也可指在空間或時(shí)間上較另一事物遠(yuǎn)的事物或人,還可指要表明的或要提及的事物、想法等。

　2.that用作關(guān)系代詞時(shí),指人或事物,同時(shí)又在從句中充當(dāng)句子成分。that偶爾也可引導(dǎo)非限制性定語(yǔ)從句。

　3.that還常用以代替who, whom, which,但that...which中的that用做關(guān)系代詞的先行詞。

　4.that用作關(guān)系代詞時(shí)在下列情況下可以省略:①引導(dǎo)限制性定語(yǔ)從句在從句中用作賓語(yǔ)時(shí); ②用在there be結(jié)構(gòu)前作主語(yǔ)時(shí); ③用作表語(yǔ)時(shí); ④在定語(yǔ)從句與先行詞之間有插入語(yǔ)時(shí); ⑤在先行詞way, reason, distance, place, office等作方式狀語(yǔ)、原因狀語(yǔ)或地點(diǎn)狀語(yǔ)時(shí)。

　5.that用作連詞時(shí)可引導(dǎo)主語(yǔ)從句、賓語(yǔ)從句、表語(yǔ)從句、同位語(yǔ)從句和狀語(yǔ)從句。

　6.that還常引導(dǎo)間接引語(yǔ)或形容詞后面的從句。

　7.that在以it作形式主語(yǔ)的句子中或引導(dǎo)賓語(yǔ)從句、狀語(yǔ)從句時(shí)?？墒÷浴?/p>

　8.that也可用于表示愿望或遺憾。

一、引導(dǎo)名詞性從句

即引導(dǎo)主語(yǔ)從句、賓語(yǔ)從句、表語(yǔ)從句和同位語(yǔ)從句，that沒(méi)有任何意義，也不作任何句子成分，只起引導(dǎo)作用。

1. 引導(dǎo)主語(yǔ)從句

由于中英語(yǔ)言文化的差異，漢語(yǔ)沒(méi)有主語(yǔ)從句。如，“英語(yǔ)很重要不是人人都認(rèn)同的?！睗h語(yǔ)語(yǔ)法認(rèn)為，“英語(yǔ)很重要”是主位詞組做句子的主語(yǔ)。而英語(yǔ)句子“That English is of vital importance is not acknowledged by all.”中，That English is of vital importance是主語(yǔ)從句。雖然that沒(méi)有任何意義，也不作任何句子成分，只起引導(dǎo)作用，但是卻不能省略。如：

That English teacher can speak fluent English is a fundamental requirement.

2. 引導(dǎo)賓語(yǔ)從句

引導(dǎo)賓語(yǔ)從句的that一般可以省略，但在以下六種情況下，一般不能省略。

（1）兩個(gè)以上的賓語(yǔ)從句并列時(shí)，從第二個(gè)從句開(kāi)始，that 不能省略。如：

Jack was informed（that）he had been enrolled in Sun Yat-sen University，and that he should register by August.

（2）介詞后引導(dǎo)賓語(yǔ)從句的that 不能省略。如：

His parents expected him nothing but/except that he can make a living by himself after graduation.

（3）主句的謂語(yǔ)動(dòng)詞與that引導(dǎo)的賓語(yǔ)從句之間有插入語(yǔ)時(shí)，that不可省略。如：

The head teacher told Jack， after a short hesitation， that he could have a day off on condition that he could make up for the missing lessons.

（4）形容詞后引導(dǎo)賓語(yǔ)從句的that一般不省略。如：

Marys parents are very content that their daughter has made such great progress in the final examination.

（5）在 it（形式賓語(yǔ)）+ adj.（補(bǔ)足語(yǔ)）+ that（賓語(yǔ)從句）結(jié)構(gòu)中， that不能省略。如：

Everyone believes it strange that he could pass the driving test.

（6）在直接引語(yǔ)中，that引導(dǎo)的賓語(yǔ)從句與主句隔開(kāi)時(shí)，that不能省略。如：

“Im sorry to say，” he said， “that you are not the suitable person for the work.”

3. 引導(dǎo)表語(yǔ)從句

表語(yǔ)從句位于連系動(dòng)詞后，引導(dǎo)表語(yǔ)從句的that一般不能省略。如：

My advice is that everyone be punctual for the appointment.

特別注意：下列句式中的that一般不能用because代替。

The reason why he was late for school is that he missed the early bus.

4. 引導(dǎo)同位從句

同位語(yǔ)從句就是在news， information， fact， word， idea等抽象名詞之后，說(shuō)明其具體內(nèi)容的從句。引導(dǎo)同位語(yǔ)從句的that一般不能省略。如：

Based on the fact that you are enthusiastic about Chinese culture， Im writing to invite you to get involved in it.

二、引導(dǎo)定語(yǔ)從句

that常被用來(lái)代替關(guān)系代詞which或who，引導(dǎo)定語(yǔ)從句。以下幾種情況，多用that而不用which或who。

1. 當(dāng)先行詞是表示事物的all， any， anything， everything， nothing或被all， any， every等修飾時(shí)。如：

Do you have anything that you are puzzled with？

All that can be done must be done.

2. 當(dāng)先行詞被形容詞的最高級(jí)或序數(shù)詞修飾時(shí)。如：

It is one of the most touching movies that have been shown this month.

The first thing that we should do is to get some food.

3. 當(dāng)先行詞有the only， the very， the same， the last 等修飾時(shí)。如：

The only thing that is impressive is his unforgettable experience in Beijing.

4. 當(dāng)主句以who或which開(kāi)頭的疑問(wèn)句時(shí)。如：

Who is the girl that is delivering a speech over there？

5. 當(dāng)先行詞既有人又有物時(shí)。如：

The writer and his novel that you have just talked about are really well known.

三、引導(dǎo)狀語(yǔ)從句

1. that 可引導(dǎo)目的狀語(yǔ)從句和結(jié)果狀語(yǔ)從句，that一般不省略。如：

The story is so touching that we will bear in our mind for a long period.

An English Speech Contest will be organized so that/ in order that students can improve their oral English.

四、用作替代詞

My seat is next to that of Marys.

The temperature in Guangdong is higher than that in Beijing.

五、用作副詞

Thanks for your encouragement， but actually my handwriting isnt that beautiful.

六、 用在強(qiáng)調(diào)句型中

It was what you said that sparked his motivation to work hard.

七、用在一些成語(yǔ)中

1. like that 像這樣

Do you usually speak to your parents like that？

2. Thats it. 說(shuō)對(duì)了。

Thats it. Youve described exactly what I felt about the film.

3. Thatthat. 情況就是如此。

Well， the only task for you is to clean the blackboard in time， and thats that.

4. with that接著，然后

He said goodbye to me and with that he left.